1. If you stare into each other’s eyes for long periods
A study out of the University of Massachusetts, back in 1989, had participants work together in pairs and stare into each other’s eyes for several minutes found that long periods of eye contact can connect you to someone and even ignite feelings of love inside you for that person you have never previously met.”
2. If you’re always around them
Ever liked a song after having heard it several times, despite not liking it initially? Well, the same thing can happen when it comes to falling in love.
It’s something known as the “exposure effect,” explains dating psychologist Madeleine Mason Roantree.
“By simply being exposed to the same stimuli (this could be an object or a person), we are more likely to have a positive attitude towards that stimuli,” she adds.
“It is believed to be because of a sense of fluency or ease with which think about something…Simply crossing someone’s path enough times, whether that be bumping into them in the supermarket or passing by on the street, might initiate attraction.”
3. If you look similar enough to their current or last partner
In one 2011 study, researchers found that both men and women rated opposite-sex faces more attractive when they closely resembled their current or most recent partners. Men, however, were less attracted to faces that looked similar to their current partner than women were.
4. If you make eco-friendly purchases
A 2016 study found that those who make environmentally friendly purchases were seen by both sexes as more desirable for long-term relationships, while those who make luxury purchases are perceived as more physically attractive and more desirable for short-term relationships.
The study notes, “Compared to luxury purchasers, eco-friendly purchasers were ascribed greater warmth, competence, and good partner traits, but less physical appeal, and they were preferred for long-term but not short-term relationships.
5. If you have a dog
Particularly relevant for men, a 2008 study followed a 20-year-old who attempted to obtain the phone numbers of women with and without a dog by his side. He found that having a dog during such social interactions increased the likelihood of obtaining their number when compared to not having one.
Also, a 2014 study, found that women who were shown stories of various men rated those men with dogs as more suitable long-term partners as well as more approachable compared to the men who didn’t.
6. If you smell right
A University of Southern California study of women who were ovulating suggested that some prefer the smell of T-shirts worn by men with high levels of testosterone.
This matched with other hormone-based instincts: Some ovulating women also preferred men with a strong jawline.
7. If you’re really, really similar to them
According to decades of studies, there’s a tendency of people to be attracted to others who are similar to themselves in important respects.
It is known as the similarity-attraction effect.
“Partners who are similar in broad dispositions, like personality, are more likely to feel the same way in their day-to-day lives,” said Gian Gonzaga, lead author of a study of couples who met on eHarmony. “This may make it easier for partners to understand each other.”
The studies generally found that this was true for long-term partners and married couples as opposed to new ones.
8. If you display the right facial expression
In 2011, researchers conducted experiments on more than 1,000 people, showing them photographs of members of the opposite sex and asking them how attractive the people in the photos were. Results showed that men rated women most attractive when they looked happy and least attractive when they displayed pride. Women, on the other hand, rated men most attractive when they displayed pride and least attractive when they looked happy.
Interestingly, shame was ranked pretty attractive in both men and women.
9. If you look like their opposite-sex parent
The University of St. Andrews psychologist David Perrett and his colleagues found that some people are attracted to folks with the same hair and eye color of their opposite-sex parents.
“We found that women born to ‘old’ parents (over 30) were less impressed by youth, and more attracted to age cues in male faces than women with ‘young’ parents (under 30),” the authors wrote. “For men, preferences for female faces were influenced by their mother’s age and not their father’s age, but only for long-term relationships.”
10. If you respond to their “bids” for attention and they do the same for you
Psychologist John Gottman, who has studied intimate relationships for over 40 years, says growing a relationship comes down to what he calls “bids.”
Gottman refers to bids as “the fundamental unit of emotional communication.” Bids can be small or big, verbal or nonverbal. They’re requests to connect. They might take the form of an expression, question, or physical outreach. They can be funny, serious, or sexual.
For example, if a bird-loving wife points out to her husband that a goldfinch just landed in a nearby tree, he can “turn away” from her by dismissing the remark or “turn toward” her by sharing her enthusiasm.
As Emily Esfahani Smith reported in the Atlantic, the results of the “bids” are staggering: in one of Gottman’s studies of marriage, couples who divorced after six years had the “turn toward” reply 33% of the time, and the couples that were still together had the “turn toward” 87% of the time.